title: Isolation and functional characterization of a delta 6-desaturase gene from the pike eel (Muraenesox cinereus).
abstract: Stearidonic acid (STA; 18:4n-3) and γ-linolenic acid (GLA; 18:3n-6) are significant intermediates in the biosynthetic pathway for the very-long-chain polyunsaturated fatty acids of eicosapentaenoic acid (EPA; 20:5n-3) and arachidonic acid (ARA; 20:4n-6), respectively. To develop a sustainable system for the production of dietary polyunsaturated fatty acids, we focused on the action of the enzyme delta 6-desaturase (D6DES) on the essential acids, linoleic acid (LA; 18:2n-6) and α-linolenic acid (ALA; 18:3n-3). A 1,335-bp full-length cDNA encoding D6DES (McD6DES) was cloned from Muraenesox cinereus using degenerate PCR and RACE-PCR methods. To investigate the enzymatic activity of McD6DES in the production of n-6 and n-3 fatty acids, a recombinant plasmid expressing McD6DES (pYES-McD6DES) was transformed into and expressed in Saccharomyces cerevisiae. The exogenously expressed McD6DES produced GLA and STA at conversion rates of 14.2% and 45.9%, respectively, from the exogenous LA and ALA substrates. These results indicate that McD6DES is essentially a delta 6-desaturase involved in very-long-chain polyunsaturated fatty acid synthesis.
authors.affiliation: National Academy of Agricultural Science, Rural Development Administration, Suwon, 441-707, Republic of Korea.
authors.forename: Sun Hee
authors.initials: SH
authors.lastname: Kim
authors.forename: Kyung Hee
authors.initials: KH
authors.lastname: Roh
authors.forename: Jung-Bong
authors.initials: JB
authors.lastname: Kim
authors.forename: Kwang-Soo
authors.initials: KS
authors.lastname: Kim
authors.forename: Nam Shin
authors.initials: NS
authors.lastname: Kim
authors.forename: Hyun Uk
authors.initials: HU
authors.lastname: Kim
authors.forename: Kyeong-Ryeol
authors.initials: KR
authors.lastname: Lee
authors.forename: Jong-Sug
authors.initials: JS
authors.lastname: Park
authors.forename: Jong-Bum
authors.initials: JB
authors.lastname: Kim
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D004524:Eels / Q000235:genetics*; D015525:Fatty Acids, Omega-3 / Q000378:metabolism; D029941:Fish Proteins / Q000737:chemistry* / Q000235:genetics / Q000302:isolation & purification / Q000378:metabolism*; D050602:Linoleoyl-CoA Desaturase / Q000737:chemistry* / Q000235:genetics / Q000302:isolation & purification / Q000378:metabolism*; D008969:Molecular Sequence Data; D016415:Sequence Alignment; D017965:gamma-Linolenic Acid / Q000378:metabolism
chemical_list: D015525:Fatty Acids, Omega-3; D029941:Fish Proteins; D017965:gamma-Linolenic Acid; D050602:Linoleoyl-CoA Desaturase; C062895:stearidonic acid